Multicast inference of packet delay variance at interior network links

End to end measurement is a common tool for network performance diagnosis, primarily because it can reflect user experience and typically requires minimal support from intervening network elements. Challenges in this approach are: (i) to identify the locale of performance degradation; and (ii) to perform measurements in a scalable manner for large and complex networks. In this paper we show how end-to end delay measurements of multicast traffic can be used to estimate packet delay variance on each link of a logical multicast tree. The method does not depend on cooperation from intervening network elements; multicast probing is bandwidth efficient. We establish desirable statistical properties of the estimator, namely consistency and asymptotic normality. We evaluate the approach through model based and network simulations. The approach extends to the estimation of higher order moments of the link delay distribution